Process of preparation of azo dyestuffs



Patented Nov. 22, 1927."

UNITED STATES PATENT J OFFICE.

WILHELM NEELMEIER, OF LEVERKUSEN,

NEAR COLOGNE, AND TEEODOR NOi'JKE-Iif,

OF WIESDORF, NEAR COLOGNE, GERMANY, ASSIGNORS TO GRASSELLI DYESTUFI CORPORATION, OF NEW YORK, N. Y., A CORPORATION 01 DELAWARE, I

. PROCESS OF PREPARATION OF AZO DYESTUIFS. I

No Drawing. Application filed May 7, 1926, Serial No. 107,486, and in Germany Kay 12, 1925..

This invention relates to a process for preparing azo dyestuffs.

00,11, no NHOSHI OOgHi The dyestufi is precipitated with sodium chloride. It is identical with the dyestufi descr'ibedin Example 1 of U. S. Patent No. 1,602,776.

(2) The diazo solution prepared accordl 7 ing to Example 2 of U. S. Patent No. 1,602,776 from 510.5 parts by weight of anilin-2.5-disulfonic acid-azo-3-amino-4-cresolequation:

"( 1) The diazo solution prepared in the usual way from 137 parts by weight of o-phenetidine, 69 parts by weight of sodium nitrite, and the required amount of hydrochloric acid, is allowed to run with stirring into a solution .cooled to 0 of 391 parts by vweight of the disodium salt of l-ethylamino- 8-naphth0l-3.6 disulfonic acid, in 2000 parts by weight of water and 106 parts by weight of soda. When the coupling is finished the dyestufl' is salted out with sodium chloride and suction filtered. It is then dissolved in 1000 parts by weight of water and treated with 106 parts by weight of soda. Then p-toluolsulfochloride is added in small portions at until the color .of the solution no 3 longer becomes more red. The reaction may be graphically illustrated. by the following N-N zomvO-om +-m. ooi

mole om. p

- N/OIHI a 2mm co,

mos mm ethylether having most probablythe formula OgNn p 1 is run into a-solution of 2 5 parts by weight with 164 parts by weight of sodium acetate.-

' NaOaS I i I aNa I on, I

mots

N-N N=N BO'N CnHl N30.

The dyestuft is salted out with sodium chloride and, if necessary, it is re-dissolved.

It is identical with the dyestufi described in I Example 2 of U. S. Patent No. 1,602,776.

This application is a continuation in part of our copending application, Serial No.

' 6658 filed February 3, 1925, which has now matured into U. S. Patent No. 1,602,776, dated October 12, 1926.

We claim: I

1. The process of producing new azodyestufis which comprises treating the reactlon product. formed by combining a diaz otized aromatic amine and an alkylamino-naphtholsulfonic acid, with an varylsulfochloride in the presence of a mineral acid binding agent.

v2. The process of producinga new azodyestuff which comprises treating the reaction product formed by combining diazotized alim'ne 2.5 disulfonic acid-azo 3 amino-4- crcsolethylether and -2-rnethylaniino-8-naph-;

thol-6-sulfonic acid, with salicylic acidsulfochloride in the presence of a mineral acid binding agent.

NHOHa a The reaction may be graphically illustrated by the following equation:

+ NBC! CHzCOOH 3. As a I new product, the azodyestufi which is substantially identical with the dyestufi obtainable by treating the reaction product formed by combining diazotized aniline-2.5-disulfonic acid-azo 3 amino-4- cresol-ethylether and 2-methylamino-8-naphthol-6-sulfonic acid, with salicylic acid sulfochloride inthe presence of a reagent which combines with acid, which dyestufi is a bronzy-bluish violet 'powder, soluble in water with a bluish-violet color, soluble in concentrated sulphuric acid with a blue color, dyeing Wool in an acid bath bluish-violet shades which are not much changed by after-chroming, and which printed on cotton with chrome acetate produces bluish-violet shades of excellent fastness to chlorine and washing.

In testimony whereof, we afiix our signatures. 

